The museum is showing works from the Triton Foundation as part of its 20th anniversary celebrations.

Museum spokeswoman Patricia Wessels told the AFP news agency that police were alerted during the night when the alarm went off but that the thief, or thieves, had left the premises by the time police arrived.

It is the biggest art theft in the Netherlands since 20 paintings were stolen from Amsterdam's Van Gogh museum in 1991, the BBC reports